Effects of red blood cell transfusion on patients undergoing cardiac surgery in Queensland - a retrospective cohort study.

BACKGROUND: Packed red blood cell (pRBC) transfusion is a relatively safe and mainstay treatment commonly used in cardiac surgical patients. However, there is limited evidence on clinical effects of transfusing blood nearing end-of shelf life that has undergone biochemical changes during storage. OBJECTIVE: To investigate evidence of associations between morbidity/mortality and transfusion of blood near end of shelf-life (> 35 days) in cardiac surgical patients. METHODS: Data from the Queensland Health Admitted Patient Data Collection database 2007-2013 was retrospectively analysed. Coronary artery bypass graft and valvular repair patients were included. Multivariable logistic regression was used to examine the effect of pRBC age (< 35 days vs. ≥ 35 days) on in-hospital mortality and morbidity. As secondary analysis, outcomes associated with the number of pRBC units transfused (≤ 4 units vs. ≥ 5 units) were also assessed. RESULTS: A total of 4514 cardiac surgery patients received pRBC transfusion. Of these, 292 (6.5%) received pRBCs ≥ 35 days. No difference in in-hospital mortality or frequency of complications was observed. Transfusion of ≥ 5 units of pRBCs compared to the ≤ 4 units was associated with higher rates of in-hospital mortality (5.6% vs. 1.3%), acute renal failure (17.6% vs. 8%), infection (10% vs. 3.4%), and acute myocardial infarction (9.2% vs. 4.3%). Infection carried an odds ratio of 1.37 between groups (CI = 0.9-2.09; p = 0.14) and stroke/neurological complications, 1.59 (CI = 0.96-2.63; p = 0.07). CONCLUSION: In cardiac surgery patients, transfusion of pRBCs closer to end of shelf-life was not shown to be associated with significantly increased mortality or morbidity. Dose-dependent differences in adverse outcomes (particularly where units transfused were > 4) were supported.

Worldwide application and valuation of extracorporeal membrane oxygenation support during the COVID-19 pandemic (WAVES).

OBJECTIVE: The outcomes of COVID-19 patients on venovenous extracorporeal membrane oxygenation (VV-ECMO) varied. We aim to investigate the variability concerning location and timeframe. We conducted a retrospective analysis of data from 351 institutions in 53 countries. The primary outcome was survival to hospital discharge or death up to 90 days from ECMO start. The associations between calendar time (month and year) of ECMO initiation and the primary outcome were examined by Cox regression modeling. Multivariable survival analyses were adjusted for the time of ECMO start, age, body mass index, APACHE II, SOFA, and the duration of mechanical ventilation before ECMO. RESULTS: 1060 adult COVID-19 patients enrolled in the COVID-19 Critical Care Consortium (COVID Critical) international registry and required VV-ECMO support. The study period is from January 2020 to December 2021. The median age was 51 years old, and 70% were male patients. Most patients were from Europe (39.3%) and North America (37.4%). The in-hospital mortality of the entire cohort was 47.12%. In North America and Europe, there was an increased probability of death from May 2020 through February 2021. Latin America showed a steady rate of survival until late in the study. South Asia, the Middle East, and Africa showed an increased chance of mortality around May 2020. In the Asian-Pacific region, after February 2021, there was an increased probability of death. The time of ECMO initiation and advanced patient age were associated with increased mortality. CONCLUSION: Variability in the outcomes of COVID-19 patients on VV-ECMO existed within different regions. This variability reflects the differences in resources, policies, patient selection, management, and possibly COVID-19 virus subtypes. Our findings might help guide global response in the future by early adoption of patient selection protocols, worldwide policies, and delivery of resources.

Hemorrhage and thrombosis in COVID-19-patients supported with extracorporeal membrane oxygenation: an international study based on the COVID-19 critical care consortium.

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) is a rescue therapy in patients with severe acute respiratory distress syndrome (ARDS) secondary to COVID-19. While bleeding and thrombosis complicate ECMO, these events may also occur secondary to COVID-19. Data regarding bleeding and thrombotic events in COVID-19 patients on ECMO are sparse. METHODS: Using the COVID-19 Critical Care Consortium database, we conducted a retrospective analysis on adult patients with severe COVID-19 requiring ECMO, including centers globally from 01/2020 to 06/2022, to determine the risk of ICU mortality associated with the occurrence of bleeding and clotting disorders. RESULTS: Among 1,248 COVID-19 patients receiving ECMO support in the registry, coagulation complications were reported in 469 cases (38%), among whom 252 (54%) experienced hemorrhagic complications, 165 (35%) thrombotic complications, and 52 (11%) both. The hazard ratio (HR) for Intensive Care Unit mortality was higher in those with hemorrhagic-only complications than those with neither complication (adjusted HR = 1.60, 95% CI 1.28-1.99, p < 0.001). Death was reported in 617 of the 1248 (49.4%) with multiorgan failure (n = 257 of 617 [42%]), followed by respiratory failure (n = 130 of 617 [21%]) and septic shock [n = 55 of 617 (8.9%)] the leading causes. CONCLUSIONS: Coagulation disorders are frequent in COVID-19 ARDS patients receiving ECMO. Bleeding events contribute substantially to mortality in this cohort. However, this risk may be lower than previously reported in single-nation studies or early case reports. Trial registration ACTRN12620000421932 ( https://covid19.cochrane.org/studies/crs-13513201 ).

Fibrinogen levels in severe trauma: A preliminary comparison of Clauss Fibrinogen, ROTEM Sigma, ROTEM Delta and TEG 6s assays from the FEISTY pilot randomised clinical trial.

OBJECTIVE: To describe the relationships between different methods of measuring functional fibrinogen levels in severely injured, bleeding trauma patients across multiple timepoints during hospitalisation. METHODS: In 100 adult trauma patients enrolled in the FEISTY pilot randomised clinical trial at four tertiary trauma centres in Australia, blood samples were collected prospectively. Consistency of agreement was calculated, comparing functional fibrinogen levels measured by four methods - ROTEM® Delta and Sigma FIBTEM A5, TEG® 6s CFF MA, and gold-standard Clauss Fibrinogen. RESULTS: Comparing the ROTEM® Delta and new-generation ROTEM® Sigma machine, consistency of agreement for FIBTEM A5, measured by calculating intraclass correlation coefficients (ICCs), was ≥0.73 across all analysed timepoints, with mean differences (Sigma minus Delta) of 0.10-3.57 mm. Corresponding values comparing the ROTEM® Sigma FIBTEM A5 and TEG® 6s CFF MA were ICC = 0.55-0.82 and ICC = 4.69-7.97 (CFF MA minus A5). Comparing ROTEM® Sigma FIBTEM A5 and Clauss Fibrinogen Analysis (CFA), among statistically significant simple linear regression models, R2 was 0.25-0.67, and comparing TEG® 6s CFF MA and CFA (CFA) 0.65-0.82, although not all differences were significant with the latter comparison. Relationships across all timepoints combined were Clauss Fibrinogen (CF) (g/L) = 0.21𝑥 + 0.004 (where 𝑥 = ROTEM® Sigma FIBTEM A5 in mm) and (g/L) = 0.16𝑥 - 0.06 (where 𝑥 = TEG® 6s CFF MA in mm). CONCLUSIONS: The present study revealed acceptable agreement between four different assays measuring functional fibrinogen, with current- and previous-generation ROTEM® machines (Sigma, Delta) performing similarly measuring functional fibrinogen via FIBTEM assay. This suggests that haemostatic resuscitation algorithms designed for the ROTEM® Delta can be applied to the ROTEM® Sigma to guide fibrinogen replacement.

Perioperative stroke.

Ischaemic or haemorrhagic perioperative stroke (that is, stroke occurring during or within 30 days following surgery) can be a devastating complication following surgery. Incidence is reported in the 0.1-0.7% range in adults undergoing non-cardiac and non-neurological surgery, in the 1-5% range in patients undergoing cardiac surgery and in the 1-10% range following neurological surgery. However, higher rates have been reported when patients are actively assessed and in high-risk populations. Prognosis is significantly worse than stroke occurring in the community, with double the 30-day mortality, greater disability and diminished quality of life among survivors. Considering the annual volume of surgeries performed worldwide, perioperative stroke represents a substantial burden. Despite notable differences in aetiology, patient populations and clinical settings, existing clinical recommendations for perioperative stroke are extrapolated mainly from stroke in the community. Perioperative in-hospital stroke is unique with respect to the stroke occurring in other settings, and it is essential to apply evidence from other settings with caution and to identify existing knowledge gaps in order to effectively guide patient care and future research.